1. Field of the Invention
This invention relates to a recording/reproducing apparatus which records video and audio signals and is particularly suitable for high-quality editing of the records on narrow tracks.
2. Description of the Prior Art
It is a common practice for a video tape recorder (hereinafter abbreviated as a VCR) to eliminate guard bands between the video tracks on a recording medium by means of an azimuth loss for more efficient use of a tape. Moreover, improved performances of a recording medium and a magnetic head have accelerated a trend toward a narrower width recording track.
Editing the records on these narrow tracks may, however, be accompanied by a tracking error inducing an error of the track linearity due to inexact mechanical fitting or adjustment error, and a pitch error due to inaccurate tape feeding at the time of editing, etc. This tracking error deteriorates the continuity of a tape pattern at the beginning and/or end of an edited point, causing a reduction in recording track width or incomplete erasure of the signals intended to be edited.
This deterioration of a tape pattern diminishes the reproduction signal amplitude at the edited point and/or invites disturbed signals, resulting in some problems including disturbances of a reproduced image at the beginning or end of an edited point and an error rate increase during digital recording.
A VCR used for editing in particular, in which a track pitch cannot be diminished to secure editing performances still fails to avail itself of the improved performances of a recording medium and a magnetic head which have realized narrower tracks.
Some of the methods of securing editing performances for the records on these narrow tracks have already been disclosed in the Japanese Laid-open Patent Application No. 1-106382 (1989) and No. 2-214001 (1990).
Japanese Laid-open Patent Application No. 1-106382 describes a rotary-head magnetic recording/reproducing apparatus, wherein recording signals are divided into editing units, the signals in each editing unit are recorded using more than one track, and one or more unrecorded editing tracks are provided in each editing unit on a recording medium.
In the above method, however, since N times (N is an integral number of 2 or more) the amount of recording signal information on a track is recorded as an editing unit and one or more recorded editing tracks are provided in each editing unit, in recording signals with a very small amount of information such as an audio signal, a time code signal, and other additional information, a tape is less efficiently used because of a greater portion of the unrecorded editing tracks in the whole area of the tape.
On the other hand, Japanese Laid-open Patent Application No. 2-214001 relates to a recording/reproducing apparatus, wherein a guard band is formed, when signals are recorded using a multi-channel head during each scan by a rotary-head cylinder by adjusting the height at which the head is mounted on the rotary cylinder, thereby allowing this guard band to absorb a tracking error at the time of editing.
The above method is effective when video tracks are formed in an editing unit by a single scan. A problem is, however, that, even in forming video tracks of signals in an editing unit by multiple scanning, a guard band is formed during each scan regardless of the editing points, resulting in less efficient use of a tape.